In a typical ink jet recording or printing system, ink droplets are ejected from a nozzle at high speed towards a recording element or medium to produce an image on the medium. The ink droplets, or recording liquid, generally comprise a recording agent, such as a dye or pigment, and a large amount of solvent. The solvent, or carrier liquid, typically is made up of water, an organic material such as a monohydric alcohol, a polyhydric alcohol or mixtures thereof.
An ink jet recording element typically comprises a support having on at least one surface thereof an ink-receiving or image-recording layer, and includes those intended for reflection viewing, which have an opaque support, and those intended for viewing by transmitted light, which have a transparent support.
While a wide variety of different types of image-recording elements for use with ink jet devices have been proposed heretofore, there are many unsolved problems in the art and many deficiencies in the known products which have severely limited their commercial usefulness. The requirements for an image recording medium or element for ink jet recording are very demanding.
It is well known that in order to achieve and maintain photographic-quality images on such an image-recording element, an ink jet recording element must:
Be readily wetted so there is no puddling, i.e., coalescence of adjacent ink dots, which leads to nonuniform density PA1 Exhibit no image bleeding PA1 Provide maximum printed optical densities PA1 Exhibit the ability to absorb high concentrations of ink and dry quickly to avoid elements blocking together when stacked against subsequent prints or other surfaces PA1 Provide a high level of gloss and avoid differential gloss PA1 Exhibit no discontinuities or defects due to interactions between the support and/or layer(s), such as cracking, repellencies, comb lines and the like PA1 Not allow unabsorbed dyes to aggregate at the free surface causing dye crystallization, which results in bloom or bronzing effects in the imaged areas PA1 Have an optimized image fastness to avoid fade from contact with water or radiation by daylight, tungsten light, or fluorescent light PA1 a) a nonionic, water-dispersible, condensation polymer gloss-enhancing layer; and PA1 b) an ink receptive layer for an ink jet image.
A desirable attribute for such an image-recording element is high gloss. High gloss is generally accomplished by either 1) melt extruding a resin, typically polyethylene, onto a fiber paper support or 2) by cast coating, a coating technique whereby the coating is pressed against a heated drum having a mirror-finished surface. While resin coating produces image-recording elements that have high gloss, this process requires specialized extrusion equipment, and a separate coating operation, and is therefore costly. Cast-coated papers are comparable in cost or slightly less expensive than resin-coated papers but require a special coating technique whereby the coating is treated with pressure and heat. Therefore, there is a need for a low cost, glossy image recording element that is easily manufactured without specialized coating equipment.